I have two other user profiles which I use for testing purposes in the Lounge. I have three domains hosted with 1and1.co.uk and it appears that email notifications sent to accounts at these domains do not arrive.

As a test, I changed the email address of one test account to a googlemail.com address. Validation instructions were received immediately. I tried changing it back to the original address and have received nothing.

Can anyone explain why notifications should be received at googlemail.com but not at 1and1.co.uk? (And no, it is not in any Spam filter.)

The Windows Secrets office is closed Dec. 24–Jan. 3 and all of the staff are on paid vacation days for the Christmas holiday. Steph and Robert and I have volunteered to come into the office every few days and check everything, but there won't be any programmer support in this forum until Jan. 4. Despite the holiday, we have pulled in help to deal with crises, such as the incorrect IP addresses that were being seen after the move to the scalable server on Dec. 22. But other issues that have stacked up will be handled as soon as people are back from their week off.

It's unclear why e-mail notifications would be received at one address but not another. There is a lower volume of posts during Christmas week, in case that explains any of the missing notifications.

Seems to be working fine again now - thanks! Notifications and password recovery email are being received.

Do you know what was up? 1and1 were going through the motions of registering as a user to test the system, but having registered were going to wait out the potential 24hr delay first.

IP.Board seems to have been sending all mail directly from the cloud servers instead of respecting the config settings. Since these cloud servers are not meant to act as SMTP servers, some block lists automatically assume any email coming from them is spam (the same reason notifications were down at the beginning of last year). Because of this, IP.B is configured to send mail through an external relay, but I think it was ignoring the override settings because it was finding a viable, local SMTP server. So I shut down the sendmail service and mails started flowing again with all the right header information (though there is one flag that gmail adds and I'm going to look into that).

Once the local SMTP server was no longer there, I guess IP.Board had to look for alternatives and it then found the proper SMTP server in its configuration. I'm waiting to hear back from our network consultants about the reason emails stopped flowing properly, but it seems to be fixed for now.